The reaction enthalpy of solid solid coordination reaction of 8 hoxine with zinc acetate is determined by solution calorimetry in an isoperibel reaction calorimeter. The calorimetric solvent is the solution of hydrochloric acid (4 mol·L\+\{-1\}). According to the results, the value Δ \-r H \+\+\-\-m=-1.002 kJ·mol\+\{-1\} Δ \-f H \+\+\-\-m(Zn(oxin)\-2·H\-2O)=-582.123 kJ·mol\+\{-1\} are recommended. \;